[PULL 54/59] linux-user: Honor TARGET_ARCH_HAS_SA_RESTORER in do_syscall

[Laurent Vivier]

From: Richard Henderson <richard.henderson@linaro.org>

Do not access a field that may not be present.  This will
become an issue when sharing more code in the next patch.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210422230227.314751-5-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/syscall.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 15b3af257bef..a2e18b06c6d0 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -9038,7 +9038,9 @@ static abi_long do_syscall1(void *cpu_env, int num, 
abi_long arg1,
                 act._sa_handler = old_act->_sa_handler;
                 target_siginitset(&act.sa_mask, old_act->sa_mask);
                 act.sa_flags = old_act->sa_flags;
+#ifdef TARGET_ARCH_HAS_SA_RESTORER
                 act.sa_restorer = old_act->sa_restorer;
+#endif
                 unlock_user_struct(old_act, arg2, 0);
                 pact = &act;
             } else {
@@ -9051,7 +9053,9 @@ static abi_long do_syscall1(void *cpu_env, int num, 
abi_long arg1,
                 old_act->_sa_handler = oact._sa_handler;
                 old_act->sa_mask = oact.sa_mask.sig[0];
                 old_act->sa_flags = oact.sa_flags;
+#ifdef TARGET_ARCH_HAS_SA_RESTORER
                 old_act->sa_restorer = oact.sa_restorer;
+#endif
                 unlock_user_struct(old_act, arg3, 1);
             }
 #endif
-- 
2.31.1